Gospels of Henry the Lion: 12th century, $11.2 million

Henry the Lion went on many fun and educational adventures with his friends Arthur the Aardvark, Barney the Dinosaur, and Clifford the Big Red Dog. Either that or he was a Welf (yes, Welf) Duke of Saxony who razed the city of Bardowick as retribution for its disloyalty (We always get those confused).